Fireproof stair.



G. W. BROOKS.

FIRBPROOP STAIR.

APPLICATION FILED AUG. 10, 1912.

1,064,050. Patented June 10,1913.

2 SHEETS-SHEET 1.

WITNESSES COLUMBIA PLANOORAPN cu., WASHINGTON, D. c,

G. W. BROOKS.

FIREPROOF STAIR.

APPLICATION FILED AUG. 10, 1912 Patented June 10, 1913.

2 SHEBTSr-SHEET 2.

um/M501 Qtfovuu COLUMBIA PLANOORAPH CDUWASNINGTON. D. c

GEORGE W. BROOKS, OF TOPEKA, KANSAS.

FIREPROOF STAIR.

Specification of Letters Patent.

Patented June 10, 1913.

Application filed August 10, 1912. Serial No. 714,394.

To all whom it may concern Be it known that I, Gnonon \V. .Bnoons, acitizen of the United States of America, and resident of Topeka, in thecounty of Shawnee and State of Kansas, have in vented certain new anduseful Improvee ments in Fireproof Stairs, of which the following is aspecification.

This invention relates to certain new and useful improvements infireproof stairs of that class in which iron or other suitable metal, inthis instance preferably pressed steel, is employed in the constructionof the stairs, combined with concrete or cement or the like, and it hasfor its objects among others to provide a simple, light, strong, durableand efficient stair, the parts of which may be readily assembled.

The stringer is formed of a sheet of metal bent into such shape as toleave a projection, behind which is placed reinforcing steel or othersuitable material. l/Vhen concrete is applied, the projection forms abinder which holds the concrete securely in place. The stair treads aremade separately, thus pcrmitting of their being made of heavy material,to give the necessary strength to wide treads. The stair riser is madeadjustable so as to be raised or lowered to suit the finished floor lineand is securely locked or retained in place. The riser is formed in suchmanner as to leave only the edge of the steel exposed to wear, thusavoiding the flat surface heretofore necessary, which was exposed towear, soon becoming smooth and slippery. The riser has an offset at thetop of the concrete which eliminates a sharp corner and preventsaccumulation of dirt and renders the stairs more sanitary.

Other objects and advantages of the invention will hereinafter appearand the novel features thereof will be particularly pointed out in theappended claims.

The invention is clearly illustrated in the accompanying drawings,which, with the numerals of reference marked thereon, form a part ofthis specification, and in which- Figure 1 is a top plan view of anumber of stairs, with portions broken away and parts in section,constructed in accordance with the present invention. Fig. 2 is a sideelevation with parts broken away. Fig. 3 is a longitudinal section as onthe line 3-3 of Fig. 1. Fig. 4. is a perspective detail showing aportion of one of the stair treads. Fig. 5 is a perspective detailshowing a portion of one of the risers. Fig. (3 is a detail in verticalsection showing the interengagement of the riser and tread. Fig. 7 is asectional detail showing a plain bent channel stringer. Fig. 8 is asimilar view of another form of stringer. Fig. 9 is a similar viewshowing a modified form of cement filled stringer. Fig. 10 is aperspective view of a modified form of tread and riser support. Fig. 11is a vertical section of a modification. Fig. 12 is a detail inperspective section of the form oil. riser seen in Fig. 11. Fig. 13 is apersperaive detail of the tread shown in Fig. 11.

Like numerals of reference indicate like parts throughout the severalviews.

lie'terringtothe drawings, 1 designates the stair stringers, 2 the treadproper and 3 the riser. These constitute the improved stair and theseparts are constructed and arranged respectively as follows: Eachstringer is formed from a sheet of metal bent into the required shape,that in the present form being provided with projections 4t, 4 formingchannels, as seen in Fig. 1, which are subsequently filled with cementor concrete or the like 5 which may or may not be reinforced byreinforcing steel or the like 6. In Fig. 2, a portion of thisreinforcing metal is shown, the concrete being omitted. When thesechannels are filled with concrete, cement or the like, the projectingflanges 4- form a binder which holds the concrete securely in place, aswill be understood upon reference to Fig. 1.

The stair treads 9 are made separately, thus allowing them to be made ofheavier material, to give the necessary strength for wide treads. Theyare formed at the front edge with a vertical flange 7 and at the rearedge with a wider upstanding flange 8, as seen best in Fig. 4. The frontflange 7 is provided with the requisite number of vertical. slots 9 f0 apurpose soon to be described. The rear flange 8 is provided with a prongor tongue 10 which is pressed out of the said flange, as seen in Figs. 4and 6, 11 in Fig. 6 indicating the space from which the tongue has beenstamped or pressed.

The riser 3 is formed at its upper edge with an outwardly curved portion12, as seen best in Figs. 3 and 5. This is so formed as to leave onlythe edge of the riser exposed to wear, as will be seen upon reference toFig. 3. This avoids flat surfaces as heretofore, which have been exposedto wear and which soon becomes smooth and slippery and thus liable tocause accident-s. The riser is provided near its upper end with aplurality of openings, as 13, for the passage of the rivets or othermeans which secures it to the front flange of the tread. Near its lowerend the riser is provided with an ofifset portion 14, as seen clearly inFigs. 8, 5 and 6.

In assembling the parts, the stringers are placed in position andopposite stringers are connected by suitable rods 15 which may passthrough eyes or loops or the like 16 and through the adjacent innersides of the stringers, as seen in Figs. 1 and 3. These eyes or loopsmay be on the reinforcing metal now to be described. Reinforcing metal17 is applied to the under side of the stringers, beneath the treads, asseen in Figs. 1 and 3, and then concrete, cement or the like 18 isplaced in position, as seen in said views.

Angle strips 19 are secured to the inner faces of the stringers byrivets or the like 20, as seen in Figs. 1 and 3, each strip of angleiron or steel 19 extending the full height of a riser and beneath thenext lower tread. The treads rest upon the horizontal portions of theseangle irons. The risers are placed in position. The lower end of theriser, which latter is provided with a terminal flange 21 for thispurpose, is received between the tongue 10 and the flange 8, as seen inFigs. 3 and 6. This tongue forms a projection which holds the concretepermanently in place, forming a look therefor, as will be readilyunderstood upon reference to Fig. 3. While the prong is herein shown andhas been referred to as projecting from the tread, it is evident that itmight project from the riser and accomplish the same end. This prong ortongue serves also to form a grip to hold the lower end of the riser,but in connection with the vertical slots 9 in the front flange of thetread allows vertical movement or adjustment so that it can be adaptedto the various heights between floors, to suit the finished floor line.

The offset 1 1 in the riser eliminates a sharp corner which would tendto allow the accumulation of dirt. This arrangement, as will be readilyunderstood upon reference to Fig. 3, avoids any joint at this point andthus is more sanitary.

After the treads are in place and the risers a'tfixed in position, thefront flanges 7 and the upper portions of the risers are fixed inposition by means of bolts or the like 22 which pass through theopenings 13 in the upper portions of the risers, as seen in Fig. 3. Theconcrete or cement 23 is then placed in position upon the treads, asseen in F igs; 1 and 8, reinforcing metal 2 1 being employed or not, asmay be desired.

Modifications in detail may be resorted to without departing from thespirit of the invention or sacrificing any of its advantages. Forinstance, I may employ other forms of stringers such as shown in Figs. 78 and 9, 25 in Fig. 7 designating a plain bent channel stringer for usenext to the wall. 26 in Fig. 8 designates a steel plate stringerornamented by drawn or rolled steel moldings 27 and 28 riveted to theplate. This type of stringer is designed principally for the facestringer where an ornamented effect is desired. 29 in Fig. 9 designatesa stringer somewhat similar to that shown in Fig. 1, but having thereturn flanges 30, the cement 81 being retained by these flanges. Thisstyle of stringer is preferred in many instances because it is easier tofinish the cement filling against the inch return flange than it is tofinish it against the edge of the steel as shown in Fig. 1.

In Fig. 10 the stringer 32 has the struckup tongues or lugs 33 which arereceived in the slots or openings 34 in the tread 35. This eliminatesthe use of the bent angle strips 19 for carrying the treads and risers,which bent angle strip is shown in position in Figs. 1 and 3.

36 in Fig. 12 designates a modified form of riser and 37 in Fig. 12shows a modified form of tread. This construction allows of theassembling of the stairs without the use of bolts. In this form lugs 38are struck-up or stamped out of the upwardly bent flange 89 of the treadadapted to on gage in a slot 40 in the riser near the upper edge thereofand adjacent the curved portion 11. The riser near its lower end isprovided with a horizontal flange 42, as seen in Fig. 12, and a verticalmember 13 provided with an opening 4 1 and a tongue or lug 15 adapted tofit over the upwardly bent flange 46 at the rear of the tread.

Referring to Fig. 11 there will be seen a lug 4:7 pressed out from thestringer 25, 48 designating the opening from which the said lug isstamped. This lug extends beyond the inner face of the stringer andserves to prevent passage of light between the end of the riser and theinside face of the stringer. This construction is to be used with theplastered or cemented type of stringers such as shown in Figs. 1 and 10.

These and other similar variations I should consider as coming withinthe scope of the protection prayed.

What is claimed as new is 1. In fireproof stairs, a tread having aprojecting tongue, and a riser independent of the tread and having atits lower end a flange for cooperation with Said tongue and an ottsetportion adjacent said flange, the lower edge of the riser being engagedby said tongue.

2. In fireproof stairs, a tread having a flange and an inwardly bent.tongue stamped therefrom, and a riser independent of the tread andhaving at its lower edge a flange held between said tongue and flange ofthe tread for cooperation with said tongue.

In fireproof stairs, a tread having a flange and a tongue stampedtherefrom, a riser independent of the tread and having at its lower edgea flange for cooperation with said tongue, and an offset portionadjaeent said flange the lower edge of said riser being received betweenthe tongue and flange of the tread.

t. In fireproof stairs, a tread having a flange and a tongue stampedtherefrom, a riser independent of the tread and having at its lower edgea flange 't'or eooperatien with said tongue, and an otl'set portionadjacent said flange the lower edge of said riser being received betweenthe tongue and flange of the tread, said tread having a flange at itsfront edge provided with vertical slots.

In fireproof stairs, a tread, and a riser independent thereof, the loweredge of said riser and the rear edge of the tread being provided withintegral interlocking tongue and flange said tongue projecting upwardand forming a projecting lock for the concrete.

(3. In fireproof stairs, a tread, a riser independent thereo'l', meansintegral with the tread and projecting outwardly from the rear facethereof to term a lock for the ocment and permitting oi. adjustment ofthe riser to suit the finished floor line, said tread having a frontvertical flange with vertical slot, and the riser having an outwardlycurved portion at its upper edge and an opening to receive meanscooperating with the vertical slot of the front flange of the tread.

7. In fireproof stairs, treads formed separately from each other,separately forn'ied risers, integral interlocking means on said treadsand risers, portions of which project upward above the tread to formlocks for the cement and means connecting the fronts ot' the treads withthe upper ends of the risers and permitting of vertical adjustment tosuit the finished floor line.

Signed by me at Topeka, Kans, this 2nd day of August 1912.

GEO. \V. BROOKS.

Witnesses:

IIENRY I iROUKS, 'lnno. ll". (loonuaN.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C."

